The present invention relates to an apparatus for controlling the movement of a virtual body or body part, where the virtual body or body part is a computer-based model that represents human, animal or mechanistic, form in a computer-generated virtual environment.
The form taken by the virtual environment will depend on the intended use of the system and may, for example, comprise the interior of a building for an architectural modelling application, or urban or surreal landscapes for games or other applications, around which environment a virtual body controlled by the user is moved. The form of the virtual body may vary as required by the application, from little more than a simple cursor to a detailed or stylised model of a humanoid or animal body, subject to constraint in terms of available processor power for rendering of such models. In the following, the term "virtual environment" will be used for such virtual landscapes or situations: the term "physical environment" will be used to denote the `real-world` surroundings of the user, for example a room in which the user contacts the various hardware devices, such as a head-mounted display (HMD), which provide the interface to the virtual environment. The terms "virtual body" and "physical body" should be construed accordingly.
One example of a virtual body control device in the form of a haptic glove is described in International Patent Application WO92/18925 (W. Industries). Within the virtual environment (viewed for example via HMD) the users hand appears as a cursor which undergoes changes corresponding with movement and flexure of the users hand. Contact between the cursor and objects within the virtual environment is simulated by inflating cushion portions of the glove to give a sensation of touch. Whilst the haptic glove is useful--if expensive--for relatively localised techniques (such as hands-on molecular modelling) within a virtual world where the object is to provide a sense of realism for the user via tactile feedback, the motion around the virtual environment is limited to the user's arm motion unless the glove is combined with additional devices such as bodysuits and/or treadmills to enable further movement. A problem which then arises is complexity of control for the differing devices, with the resulting requirement to memorise different operational commands or operations being at variance with achieving a state of user-immersion in the virtual environment.